Exercise: Tungsten and fluorescent lighting

For this exercise I had to find a room lit by tungsten lighting and then wait until sunset. 

When I looked out the window for a minute at the fading daylight and then looked back in the room the light was a yellowy orange colour.  It took less than a minute for my eyes to adjust and when they had the room looked a normal colour perhaps with a hint of a yellow tinge. 

Looking back out at daylight, the sky looked very blue and darker. 

I measured various points in the room with the camera's light meter.  The shutter speeds were very slow for an aperture of f/9 varying from 1.3 secs to 2 secs for a normal average exposure using ISO 200.  With the shutter wide open at f/5.6 the shutter speed was 4secs for an average exposure.  This is much too slow for handheld. 

It demonstrates that tungsten light is not very strong which I would have expected because lamps are not very bright for reading and even bigger lights on the ceiling fail to distribute a bright even light across the room.  The centre of the room underneath the light is always brightest. 

I then had to take some pictures of the room where the interior and the window with the sunset outside were visible. 

WB Auto - The room looks a little yellow

WB Daylight - the room looks orange but the outside looks a little more realistic.











WB Incandescent - looks very similar to the Auto setting. Room has a yellowish ting but is more accurate than the daylight setting.











Part 2.  Fluorescent lighting

For the second part I had to find two different interiors lit with fluorescent lighting. I had to take two images of these scenes one with the WB set to auto and the other using Fluorescent.

Although not the most interesting shots, I chose a very white background so we could see the effect of the different white balances more clearly.  In the second shot I chose a colourful composition to see if the white balance had any effect on a range of colours.

WB Auto

There is a slight green tinge to the image. I captured a white wall so this tinge could be seen clearly.

WB - Fluorescent

The green tinge is gone.  The shot is warmer and more like the way my eyes saw the scene at the time.

WB - Auto

You can see the window frame is slightly green instead of a warm cream colour.  The pink wall in the background is also a bit yellowish.

WB - Fluorescent

You can see the green and yellow tinges have been corrected.  The blue of the seats is also brighter than the shot above.